SEARCH FOR ANOMALOUS SPIN-SPIN INTERACTIONS BETWEEN ELECTRONS USING ADC SQUID

We use a paramagnetic salt TbF3 with a DC SQUID to search for possible anomalous spin-spin interaction of two rotating Dy6Fe23 polarized bod ies and two rotating HoFe3 polarized bodies with the TbF3 paramagnetic salt. We set limits on the electron-electron spin interaction. In ter ms of a standard dipole-dipole form, the limits are (1.2 +/- 2.0) x 10 (-14) for the anomalous spin-spin interaction of electrons in terms of the interaction strength between the magnetic moments of the electron s. Compared to previous results, this is a forty-fold improvement.